Fog computing makes up for the shortcomings of cloud computing. It brings many advantages, but various peculiarities must be perceived, such as security, resource management, storage, and other features at the same time. This paper investigates the resource contribution model between the fog node and cloud or users when fog computing introduces blockchain. The proposed model practices the reward and punishment mechanism of the blockchain to boost the fog nodes to contribute resources actively. The behavior of the fog node in contributing resources and the completion degree of the task also for contributing resources are packaged into blocks and stored in the blockchain system to form a transparent, open, and tamper-free service evaluation index. The differential game method is employed to model and solve the above process and address the interaction between the optimal resource contribution strategy of the fog node and the optimal benefit under the optimal resource contribution strategy. Indirectly, this service evaluation index also brings long-term economic benefits to fog service providers. Besides, taking advantage of the performance characteristics of the collective maintenance of blockchain and the ability to establish a credible consensus mechanism in an untrusted environment, fog computing nodes, under the proposed architecture, can have specific security protection capabilities.

With the large scale deployment of multihomed mobile computing devices in today’s Internet, the Multipath TCP (MPTCP) is being considered as a preferred data transmission technology in the future Internet due to its promising features of bandwidth aggregation and multipath transmission. However, MPTCP is more likely to be vulnerable to the transmission quality differences of multiple paths, which cause a “hot-potato” out-of-order arrival of packets at the receiver side, and in the absence of a related approach to fix this issue, serious application level performance degradations will occur. In this paper, we proposes MPTCP-LM ${}^3$ , a Lightweight path Management Mechanism to aid Multihomed MPTCP based mobile computing devices towards efficient multipath data transmission. The goals of MPTCP-LM ${}^3$ are: (i) to offer MPTCP a promising path management mechanism, (ii) to reduce out-of-order data reception and protect against receiver buffer blocking, and (iii) to increase the throughput of mobile computing devices in a multihomed wireless environment. Simulations show that MPTCP-LM ${}^3$ outperforms the current MPTCP schemes in terms of performance and quality of service.